Roughly 15 percent of U.S. workers are employed outside the traditional 9 a.m. to 5 p.m. work day, typically referred to as shift workers. Defined by the National Sleep Foundation, shift work is any work that occurs during evenings, overnights, rotating shifts or even the early hours of the morning.
"Shift work can add a level of convenience for some families, such as added flexibility related to child care and better pay," says Tapan Desai, MD, a Franciscan Physican Network board-certified sleep medicine and pulmonary specialist. In addition to some of the positives, he says there are drawbacks that he discusses with his patients. "Researchers have found that shift work is linked to an increased risk of heart attacks, ulcers, depression, obesity and high blood pressure, along with sleep problems, such as trouble falling asleep, trouble staying asleep and excessive sleepiness."
Researchers are studying why shift work can cause health problems. Currently at least two different causes can be blamed for these risks – lifestyle and biology.
In terms of lifestyle, shift workers may find less time to exercise regularly and may be more prone to eat a less healthy diet. These individuals also are more prone to feeling isolated, since their jobs may cut them off from family and friends.
The more significant problem with shift work has to do with biology. The body has a natural, internal clock, or circadian rhythm, that is linked to natural daylight and darkness. This rhythm tells us to sleep when it is dark and be awake when it is light. Shift work goes against most people's internal body clock.
This disruption of the natural sleep/wake cycle affects how the body functions and interferes with the natural release of hormones and chemicals in the body, leading to potential problems of the cardiovascular system, metabolism, digestion, immune system, mental health and even fertility and pregnancy.
The news is not all bad says Dr. Desai. "If you are in good health to begin with, the health risks of shift work are relatively low. Keep the risks in perspective and control what you can by making healthy lifestyle choices in the areas of diet, exercise and sleep." His tips include: